The continuation of this project will use an age-regression model to confirm that, in chronic alcoholics, certain electrophysiological, cognitive and brain structural variables show evidence of central nervous system (CNS) deficits beyond age norms. The role of age, alcohol exposure, nutritional status and family history of alcoholism in these deficits will be tested. The phenomenom of reversibility will be investigated, and factors contributing to it evaluated. The specific CNS variables to be measured include: (i) amplitude, latency, and topographic distribution of the P300, a cognitive component of the event-related potential (ERP); (ii) performance on neuropsychological tests of concept formation, visuo-spatial abilities, and memory (standardized against estimates of premorbid general intelligence); (iii) brain atrophy, quantified by measuring the proportion of cerebrospinal fluid (CSF), white matter and grey matter at anatomic regions of interest such as ventricles and cortical sulci visualized by Magnetic Resonance (MR) imaging; and (iv) brain tissue hydration, quantified by deriving T1 and T2 values for whole brain sections imaged by MR, and measuring mean values within designated regions of interest. Chronic alcoholics ranging in age from 25 - 65 will be tested during the first and fourth week of withdrawal and after an interval of 12 months. Healthy community volunteers across the same age range, will also be tested at equivalent intervals. Cross-sectional analyses will determine the extent to which alcoholics can be shown to have CNS deficits over and above those expected for their age. Within-group analysis will relate specific subject characteristics such as nutritional status, exposure to ethanol, family history of alcoholism and age, to these CNS deficits. Longitudinal analysis will determine the extent to which deficits, including brain atrophy, are reversible during a three-week period of abstinence, and what further changes are seen after one year.